CVE-2023-43655

HIGHNVD 8.88.8—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 8.8 under NVD CVSS v3. EPSS exploit probability: 1.4%, top 31% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
8.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 8.8Exploit: None knownExposed: 0

A fix is available — apply it.

Composer is a dependency manager for PHP. Users publishing a composer.phar to a public web-accessible server where the composer.phar can be executed as a php file may be subject to a remote code execution vulnerability if PHP also has register_argc_argv enabled in php.ini. Versions 2.6.4, 2.2.22 and 1.10.27 patch this vulnerability. Users are advised to upgrade. Users unable to upgrade should make sure register_argc_argv is disabled in php.ini, and avoid publishing composer.phar to the web as this is not best practice.

CVSS v3
8.8
EG Score
8.8(medium)
EG Risk
40(Track)
EG Risk 40/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity88% × 45%
Exploitation1% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
71%
KEV
Not listed

Published

September 29, 2023

Last Modified

June 17, 2026

Advisory Details (8)

Auto-updated Aug 30, 2026
Patch available. Sources: github_commit, github.
github_commit Patch Available

commit 955a48e6319c (composer/composer)

Patch available: composer/composer 2.8.5 (contains commit 955a48e6319c)

https://github.com/composer/composer/commit/955a48e6319c8962e5cd421b07c00ab3c728968c
github_commit

commit 4fce14795aba (composer/composer)

Fix landed in composer/composer commit 4fce14795aba — awaiting tagged release

https://github.com/composer/composer/commit/4fce14795aba98e40b6c4f5047305aba17a6120d
generic

[SECURITY] Fedora 37 Update: composer-2.6.5-1.fc37 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/[email protected]/message/KFOPGPW2KS37O3KJWBRGTUWHTXCQXBS2/
generic

[SECURITY] Fedora 38 Update: composer-2.6.5-1.fc38 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/[email protected]/message/7AWYAUZNH565NWPIKGEIYBWHYNM5JGAE/
generic

[SECURITY] Fedora 39 Update: composer-2.6.5-1.fc39 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/[email protected]/message/66H2WKFUO255T3BZTL72TNYJYH2XM5FG/
generic Patch Available

[SECURITY] [DLA 3777-1] composer security update

https://lists.debian.org/debian-lts-announce/2024/03/msg00030.html
github Patch Available

Remote Code Execution via web-accessible composer.phar · Advisory · composer/composer · GitHub

https://github.com/composer/composer/security/advisories/GHSA-jm6m-4632-36hf
github_commit

commit 95e091c92103 (composer/composer)

Fix landed in composer/composer commit 95e091c92103 — awaiting tagged release

https://github.com/composer/composer/commit/95e091c921037b7b6564942845e7b738f6b95c9c

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntucomposer (1.0.0~beta2-1ubuntu0.1~esm2) @ xenial2026-05-24ubuntu

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(6 across 6 ecosystems)
Debian:10(1)
PackageVulnerable rangeFixed inDependents
composer1.8.4-1, 1.8.4-1+deb10u1, 1.8.4-1+deb10u21.8.4-1+deb10u3—
Debian:11(1)
PackageVulnerable rangeFixed inDependents
composer2.0.11-1 ... 2.9.8-1 (96 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
composer2.5.5-1, 2.5.5-1+deb12u1, 2.5.5-1+deb12u2, 2.5.5-1+deb12u32.5.5-1+deb12u4—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
composer—2.6.4-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
composer—2.6.4-1—
Packagist(1)
PackageVulnerable rangeFixed inDependents
composer/composer2.3.0 ... 2.6.3 (30 versions)2.6.4—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

All Vendor Advisories

(1)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 5× in last 7d / 28× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 175 total refreshes for this CVE.

  1. 2026-09-18 19:25 UTCEPSS rescore
  2. 2026-09-17 19:25 UTCEPSS rescore
  3. 2026-09-16 14:06 UTCEPSS rescore
  4. 2026-09-16 14:06 UTCEPSS rescore
  5. 2026-09-16 05:11 UTCEPSS rescore
  6. 2026-09-13 16:44 UTCEPSS rescore
  7. 2026-09-12 14:58 UTCEPSS rescore
  8. 2026-09-11 14:50 UTCEPSS rescore
  9. 2026-09-11 09:34 UTCEPSS rescore
  10. 2026-09-08 21:58 UTCEPSS rescore
  11. 2026-09-07 15:59 UTCEPSS rescore
  12. 2026-09-06 13:45 UTCEPSS rescore
  13. 2026-09-06 13:45 UTCEPSS rescore
  14. 2026-09-05 15:26 UTCEPSS rescore
  15. 2026-09-04 13:58 UTCEPSS rescore
  16. 2026-09-04 05:04 UTCEPSS rescore
  17. 2026-09-03 17:16 UTCOSV refresh
  18. 2026-09-02 14:09 UTCEPSS rescore
  19. 2026-09-01 13:51 UTCEPSS rescore
  20. 2026-08-30 19:15 UTCEPSS rescore
  21. 2026-08-30 01:20 UTCEPSS rescore
  22. 2026-08-28 21:39 UTCEPSS rescore
  23. 2026-08-27 14:23 UTCEPSS rescore
  24. 2026-08-26 14:44 UTCEPSS rescore
  25. 2026-08-26 14:43 UTCEPSS rescore
Show 75 more
  1. 2026-08-25 13:46 UTCEPSS rescore
  2. 2026-08-23 00:17 UTCEPSS rescore
  3. 2026-08-21 23:47 UTCEPSS rescore
  4. 2026-08-20 22:53 UTCEPSS rescore
  5. 2026-08-19 17:02 UTCEPSS rescore
  6. 2026-08-19 17:02 UTCEPSS rescore
  7. 2026-08-18 13:46 UTCEPSS rescore
  8. 2026-08-17 13:45 UTCEPSS rescore
  9. 2026-08-17 06:27 UTCOSV refresh
  10. 2026-08-16 14:54 UTCEPSS rescore
  11. 2026-08-16 02:12 UTCEPSS rescore
  12. 2026-08-15 01:28 UTCEPSS rescore
  13. 2026-08-15 01:28 UTCEPSS rescore
  14. 2026-08-13 21:58 UTCEPSS rescore
  15. 2026-08-12 13:48 UTCEPSS rescore
  16. 2026-08-11 13:39 UTCEPSS rescore
  17. 2026-08-09 13:44 UTCEPSS rescore
  18. 2026-08-09 13:44 UTCEPSS rescore
  19. 2026-08-08 16:35 UTCEPSS rescore
  20. 2026-08-07 16:25 UTCEPSS rescore
  21. 2026-08-06 13:45 UTCEPSS rescore
  22. 2026-08-05 19:15 UTCEPSS rescore
  23. 2026-08-04 15:07 UTCEPSS rescore
  24. 2026-08-03 10:34 UTCEPSS rescore
  25. 2026-08-03 10:34 UTCEPSS rescore
  26. 2026-08-02 02:25 UTCEPSS rescore
  27. 2026-08-02 02:25 UTCEPSS rescore
  28. 2026-08-02 01:06 UTCOSV refresh
  29. 2026-08-01 04:14 UTCEPSS rescore
  30. 2026-08-01 04:13 UTCEPSS rescore
  31. 2026-07-30 16:26 UTCEPSS rescore
  32. 2026-07-30 16:26 UTCEPSS rescore
  33. 2026-07-30 01:28 UTCEPSS rescore
  34. 2026-07-30 01:28 UTCEPSS rescore
  35. 2026-07-28 15:34 UTCEPSS rescore
  36. 2026-07-28 15:34 UTCEPSS rescore
  37. 2026-07-26 14:52 UTCEPSS rescore
  38. 2026-07-26 14:52 UTCEPSS rescore
  39. 2026-07-25 14:16 UTCEPSS rescore
  40. 2026-07-24 14:16 UTCEPSS rescore
  41. 2026-07-23 14:16 UTCEPSS rescore
  42. 2026-07-23 14:16 UTCEPSS rescore
  43. 2026-07-23 02:26 UTCEG score recompute
  44. 2026-07-22 23:13 UTCEG score recompute▲ 2.40
  45. 2026-07-22 14:06 UTCEPSS rescore
  46. 2026-07-21 15:23 UTCEPSS rescore
  47. 2026-07-21 15:23 UTCEPSS rescore
  48. 2026-07-20 17:06 UTCEPSS rescore
  49. 2026-07-19 14:29 UTCEPSS rescore
  50. 2026-07-19 02:27 UTCEPSS rescore
  51. 2026-07-18 10:03 UTCEPSS rescore
  52. 2026-07-18 10:03 UTCEPSS rescore
  53. 2026-07-16 17:01 UTCEPSS rescore
  54. 2026-07-16 17:01 UTCEPSS rescore
  55. 2026-07-15 16:56 UTCEPSS rescore
  56. 2026-07-15 16:56 UTCEPSS rescore
  57. 2026-07-15 08:19 UTCOSV refresh
  58. 2026-07-15 01:58 UTCEPSS rescore
  59. 2026-07-13 22:28 UTCEPSS rescore
  60. 2026-07-13 22:28 UTCEPSS rescore
  61. 2026-07-13 06:11 UTCEPSS rescore
  62. 2026-07-13 06:11 UTCEPSS rescore
  63. 2026-07-12 05:45 UTCEPSS rescore
  64. 2026-07-12 05:45 UTCEPSS rescore
  65. 2026-07-11 08:26 UTCEPSS rescore
  66. 2026-07-11 08:26 UTCEPSS rescore
  67. 2026-07-09 19:08 UTCEPSS rescore
  68. 2026-07-08 15:13 UTCEPSS rescore
  69. 2026-07-07 13:44 UTCEPSS rescore
  70. 2026-07-06 16:26 UTCEPSS rescore
  71. 2026-07-06 16:26 UTCEPSS rescore
  72. 2026-07-06 02:22 UTCEPSS rescore
  73. 2026-07-05 02:29 UTCEPSS rescore
  74. 2026-07-04 06:29 UTCEPSS rescore
  75. 2026-07-01 15:05 UTCEPSS rescore

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2023-43655?
CVE-2023-43655 is a high vulnerability published on September 29, 2023. Composer is a dependency manager for PHP. Users publishing a composer.phar to a public web-accessible server where the composer.phar can be executed as a php file may be subject to a remote code execution vulnerability if PHP also has registerargcargv enabled in php.ini. Versions 2.6.4, 2.2.22 and…
When was CVE-2023-43655 disclosed?
CVE-2023-43655 was first published in the National Vulnerability Database on September 29, 2023, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2023-43655 actively exploited?
CVE-2023-43655 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 28.9% of all scored CVEs.
What is the CVSS score of CVE-2023-43655?
CVE-2023-43655 has a CVSS v3 base score of 8.8 (NVD).
How do I remediate CVE-2023-43655?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2023-43655, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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